williams



Feb. 11, 1936.

R. M. WIILLIAMS 2,030,488

CIRCUIT BREAKER Filed Nov. 6, 1930 fiQLPH/YMLL/HMS dfkomuq Patented Feb. 11, 1936 OFFICE Ralph M. Williams, Detroit, Mich alslgnor to Packard Motor Car Company, Detroit, Mich. a corporation of Michigan Application November 0, 1930, Serial No. 49am 9 Claims. (cl. 200-106) This invention relates to internal combustion engines and more particularly to the ignition system of such engines. 1

Hitherto it has been the practice in ignition system circuit-breaker construction to form the contact points of the breaker as integral parts of the stationary and removable arms. The contact points are usually of tungsten or the like, and because of the difliculty of dressing down these points when they become worn and pitted, it has been customary in shop practice to replace the stationary and movable arms by new arms. Since the arms themselves do not become worn their renewal represents an unnecessary expense.

; .It is therefore a general object of the invention to provide a novel and improved form of circuit-breaker for the ignition system of such engines, and more particularly it is an object of the invention to provide a circuit-breaker for the ignition system in which the contact points may be replaced without discarding the supporting arms or other parts of the breaker.

A still further object of the invention is to provide a circuit-breaker of the above description which shall be simple, inexpensive and reliable.

An important feature of the invention is that a plurality of contact points may be mounted on a single removable member and may be selectively I placed in operative position in the breaker.

Other and further features and objects of the invention will be more apparent to those skilled in the art, upon a consideration of the accompanying drawing and following specification wherein i is disclosed a single exemplary embodiment of the invention with the understanding, however, that such changes may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

In said drawing:

Figure 1 is a top plan view of the distributor of an internal combustion engine with the cap removed to show the improved circuit-breaker mechanism.

Figure 2 is an enlarged top plan view, partly in section, of thecircuit-breaker structure shown in Figure 1, and

Figure 3 is a side elevational view of the contact holder and contact point shown in Figure 2 taken along the line 3-3.

Referring now to the drawing for a more complete disclosure of this invention, there is shown in Figures 1 and 2 a distributor housing III, for an internal combustion engine, in which a circult-breaker for making and breaking the electric circuit of the ignition system is mounted. The circuit breaker includes a pivotally mounted arm l2 and the stationary bracket or abutment It.

The arm I! is pivotally mounted at one end thereof on the pin it so that it may be oscillated 5 to make and break the low tension circuit of the ignition system. The block I of the arm is resiliently" held against the cam II by means of a spring (not shown), and oscillation of the arm is caused by rotation of the cam in the usual manner.

The arm I! is provided at its end with a holding means in which a contact point carrying means may be engaged. The holding means preferably comprises a flanged pocket or slide ll, open at the top to permit insertion and removal of the contact point carrying means therein.

The carrying means preferably comprises a plate in the form of a disc having a pair of contact points 2| and 22, one of which is fastened to each side of the disc.

By utilizing a pair of contact points mounted on the same supporting means substitution of a new contact point for a used point is readily accomplished by removing the disc, turning it over and re-insertin'g it in the holder.

Friction alone may be depended upon to hold the disc in place, or a locking screw 23 which is threaded in the arm and is adapted to bear against the inner contact point may be utilized to secure the disc and points in place in the arm.

Substantially the same structure may be uti-" lized for the stationary contact point, but since the stationary point must be adiustablein and out with reference to the cam to permit obtaining the proper clearance between points the contact holder is preferably in the form of a hollow screw 25 threaded through the abutment ll. The screw 25 is provided with a milled head 26 to permit hand adjustment of the position of the point, and the screw may be locked in place by means of a locking nut l9. A suitably flanged slide or pocket 21 is provided on the end of the screw and a lo'cking screw 28 is threaded into the holding screw to lock the contact point in place.

It is apparent that the contact points may be readily removed and replaced in their holders and that the contact points themselves are simple and inexpensive.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is: p

1. In a circuit-breaker structure, the combination of a contact point holding screw, a slide on the end of the screw, a locking screw within 55 the holding screw, and a reversible contact point smictm'eoomprtin'gopposedcmtactiacesheld inthealiiieliythelockingscre'w.v J

2.1na circuit-breaker stnicture. thecombinationotacontactpointholdingmeam.aaiide ontheendottheholdingmeanaalockingmeans withintbeholdingmeansandaoontactpoint structure a disc and a contact pro- .iectingthroughthedisc,saiddiscbeingheldin theslidebytheiockingmeans.

$.A circuit-breaker structure comprising a contactpointholdenaslideontheendotthe holder, a plate irictionally held in the slide. a contact pointproiectingiromthesides otthe plate,andmeanstorincreasingthemctionbetweenthepla-tcandulide: V

'4. A circuit-breaker structure comprising a contact point holder,aslideontheholder.aplate i'rlctionallyhddintheslidmandapair oicontactpointsmountedoneoneachsideottheplate.

5. Inacircmt-breakeriortheignitionsystemoi an internal combustion engine, a means or providingi'orreadyreplacementoithecontact points in the contactpoint holder comprising a pair of :mdflangesonthecontaetholderandacoilange on the contact point between said opposed flanges, said flanges irlctionally engaginteaehother.

6.!naclrcuitbreakerstructmehavingamovable contact breaker arm, a slide on the breaker arm,adiscpositionedintheslide.saiddisc carryingacohtact pointoneachside thereot.lockingmeansonthebreakerarmenlsslns thedisc tomaintain it-inposltionintheslide.anxed bracket, an adjustable contact holding screw mountedinthebracketinspacedalignmentwith thecontactcarryingdismaslideontheendoi theadiustablecontactholdingscremacontact carryingdisc'within thesaidslide memberonthe adjustable screw, and a locking screw within the adjustable holding screw engaging the disc on the screw. said adjustable contact holding screw being adapted to be adjusted relatively to theilxed bracket to maintain its contact point in desired spaced relation with the contact point carried by .the breaker arm. 7. In a contact breaker structure. a movable variably fixing the position of the contact holding means with respect to the movable breaker arm to maintain the contacts in the desired relationship.

8. A reversible metal contact unit for a circuit breaker comprising a circular plate element and contact elements extending cd-axially irom op- 1 posite faces 01 the plate element, said plate and contact elements being integral.

9. In a circuit breaker, the combination 0! a pivotaily mounted arm having a pocket on its free end; and a contact element comprising a plate re- 1 molvabiy engageable in said pocket, and contact points projecting irom opposite faces of said plate, said contact element being reversible endwise in the pocket to place either contact point in eti'ective position.

RALPH M. 

